Add FilePath to base namespace.

chrome/browser/extensions/convert_web_app.h

Index: chrome/browser/extensions/convert_web_app.h
diff --git a/chrome/browser/extensions/convert_web_app.h b/chrome/browser/extensions/convert_web_app.h
index 78d80f9d53a1e1366de4b04352e9855b7328ef56..77c03d56de9537a090d84a2e9e1502499e5ac3cc 100644
--- a/chrome/browser/extensions/convert_web_app.h
+++ b/chrome/browser/extensions/convert_web_app.h
@@ -9,9 +9,8 @@
 
 #include "base/memory/ref_counted.h"
 
-class FilePath;
-
 namespace base {
+class FilePath;
 class Time;
 }
 
@@ -41,7 +40,7 @@ std::string ConvertTimeToExtensionVersion(const base::Time& time);
 scoped_refptr<Extension> ConvertWebAppToExtension(
     const WebApplicationInfo& web_app_info,
     const base::Time& create_time,
-    const FilePath& extensions_dir);
+    const base::FilePath& extensions_dir);
 
 }  // namespace extensions